Rhopalopsole vespertilio Chen & Du, 2017

Chen, Zhi-Teng, 2020, The larvae of Rhopalopsole vespertilio Chen & Du (Plecoptera: Leuctridae) with biological notes on sympatric Nemoura nankinensis Wu (Plecoptera Nemouridae), Zootaxa 4767 (4), pp. 578-588 : 579-586

publication ID	https://doi.org/ 10.11646/zootaxa.4767.4.7
publication LSID	urn:lsid:zoobank.org:pub:F54FEA66-2CCB-4F87-99B9-E1C7DB5993F7
DOI	https://doi.org/10.5281/zenodo.3796635
persistent identifier	https://treatment.plazi.org/id/03B6DC38-FFB6-FFFD-B5B6-FF1F3D13FB9E
treatment provided by	Plazi
scientific name	Rhopalopsole vespertilio Chen & Du, 2017
status

Treatment

Rhopalopsole vespertilio Chen & Du, 2017 View in CoL

Figs. 1–10 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 .

Rhopalopsole vespertilio Chen & Du, 2017 . Zootaxa, 4319(1): 185.

Material examined. Twenty-eight male adults, six female adults, one male larva, four female larvae and three exuviae, China: Jiangsu Province, Jurong City, Mt. Maoshan ( Fig. 1 View FIGURE 1 A-F), 31°47′15″N, 119°18′23″E, 160 m, 5 March 2020, leg. Zhi-Teng Chen (ICJUST).

Mature larva. Body length 7.0–8.0 mm. General color pale brown, appendages generally pale ( Figs. 2–3 View FIGURE 2 View FIGURE 3 ). Head slightly elongate, oval shaped ( Fig. 4 View FIGURE 4 A–B), frontal area with two oblique fusiform sclerites connected by anterior ocellus ( Fig. 4A View FIGURE 4 ); labrum glabrous at anterior half, medially with a transverse row of pale, short hairs, posterior half mostly spinulose but with two small glabrous areas on each side of median line; clypeus broad and elliptical, medially elevated; epicranial suture pale. Three ocelli, reddish; compound eyes dark and glabrous; several glabrous areas present near the anterior and posterior lateral ocelli. Antennae slender ( Fig. 4 View FIGURE 4 C–F), slightly shorter than half of body length, basal ⅔ covered with dense bristles and apically fringed with several short bristles, apical ⅓ nearly gla- brous, pale with very short apical spines. Mouthparts typical euholognathan, glossa and paraglossa of labium knobshaped, equally short ( Fig. 4B View FIGURE 4 ); labial palp short, three-segmented ( Fig. 4B View FIGURE 4 ); maxillary palp five segmented ( Fig. 5 View FIGURE 5 A–B); stipes of maxilla basally covered with sparse long spines; galea hook-shaped, outer margin of basal half fringed with several long bristles, apex with several short spines, inner margin glabrous; lacinia subtriangular and slightly sclerotized, with a long apical tooth and a comb with approximately 16 marginal spines. Mandible with four major unserrated apical teeth, base of the anterior pair of apical teeth with a short row of approximately 8 spines; marginal comb of about 15 thick spines posterior of the apical pair of teeth ( Fig. 5 View FIGURE 5 C–D). Mentum pale; posterior half of submentum with two oblique, elliptical pale areas ( Fig. 4B View FIGURE 4 ). Cervix short, ventral aspect with two anterolateral conical sclerites ( Fig. 4B View FIGURE 4 ). Pronotum subquadrate with obtuse corners ( Fig. 4A View FIGURE 4 ), mostly brown, covered by dense spinules, anterior and posterior transverse sutures dark. Meso- and metanota covered with sparse short bristles ( Fig. 4G View FIGURE 4 ); wing pads of mesonotum elongate, slightly constricted basally ( Fig. 4 View FIGURE 4 G–H); wing pads of metanotum shorter, widened at basal half; dorsal aspects of wing pads scattered with irregular, black, short bristles. Coxae membranous and glabrous dorsally ( Fig. 4A, G View FIGURE 4 ), but ventrally and laterally spinulose ( Fig. 4B, H View FIGURE 4 ); trochanters ventrally spinulose. Femora dorsally and ventrally covered with dense short spines except for a glabrous longitudinal median stripe ( Fig. 6 View FIGURE 6 E–F), outer margin with sparse short spines and moderately long swimming hairs which shorten towards each end of femora, inner margin with two longitudinal rows of dark spines along the two ridges. Tibiae evenly covered with short spines except for a glabrous longitudinal median stripe on apical half of dorsal and ventral surfaces, outer margin with sparse short spines and moderately long swimming hairs which shorten towards each end, inner margin with two longitudinal rows of dark spines; two large tibial spurs present ventrally. Tarsal segments spinulose, outer margins with sparse short swimming hairs. Claws sharp and slender, apically sclerotized ( Fig. 6 View FIGURE 6 A–F).

In male larvae: abdominal terga 4–7 and sterna 3–6 evenly covered with black short spines ( Figs. 2 View FIGURE 2 , 7 View FIGURE 7 A–B); terga 2–8 each with two fusiform lateral sclerites; terga 3–8 each with four small adult muscle scars visible beneath larval cuticle; anterior margins of terga 1–9 with medially interrupted adult sclerites beneath exoskeleton. Tergum 9 with long spines less in number than previous segments, two transverse sclerites of adult present beneath exoskeleton of posterior margin. Posterior half of tergum 10 glabrous, rounded and elevated, enclosing a hook-shaped epiproct. Sterna 2–6 each with two black pits and anterolateral sclerites; an elliptical adult vesicle visible below sternum 9; paraprocts mostly glabrous, basally with several dark spines, apically with a single pale, long hair on each paraproct. Cerci mostly pale, much shorter than abdomen; basal cercal segment spinulose and brown, other segments pale; each segment with several long apical bristles, length of which does not exceed the segment length ( Figs. 2 View FIGURE 2 , 8 View FIGURE 8 ).

In female larvae: abdominal terga 1–9 and sterna 1–7 evenly covered with black short spines ( Figs. 3 View FIGURE 3 , 9 View FIGURE 9 ); terga 2–8 each with two fusiform lateral sclerites; terga 2–8 each with four small dark pits; tergum 9 with two small dark pits; tergum 10 with two anterolateral sclerites and five glabrous spots, posterior margin humped. Sterna 2–3 each with two small anterolateral sclerites; posterior margin of sternum 7 with a glabrous median area; Sternum 8 with a funnel-shaped membranous area which with an inverted Y-shaped patch of long spines. Sternum 9 with two glabrous triangular areas on each side of median line. Paraprocts membranous, apically with one or two pale, long hairs on each paraproct. Cerci similar to male.

Diagnosis. Rhopalopsole vespertilio is the second Chinese species of Rhopalopsole of which the larva has been associated. As with R. hamata , larvae of R. vespertilio exhibit similar maxilla and cerci, but the mandible has larger apical teeth; the head, pronotum, and abdomen have dark brown markings; antennae and legs with apparently different spine patches (see figs. 4–7 in Chen 2019). However, since only two larvae of the 56 Chinese species have been described, any direct comparisons await further larval associations in this genus.

Biological notes. Unlike the sympatric N. nankinensis , R. vespertilio was found only in smaller (less than two meters wide) upstream sections with increase flows ( Fig. 1 View FIGURE 1 C–F). As is typical of many leuctrids, larvae of R. vespertilio were associated with leaf packs. Larvae typically exhibited serpentine movement ( Fig. 10 View FIGURE 10 A–C). Larvae moved to the upper surface of the leaves to emerge, then flew to nearby riparian vegetation ( Fig. 10 View FIGURE 10 D–G). After emergence, larvae darkened with the first color change occurring with the pronotum ( Fig. 10 View FIGURE 10 H–J). No obvious drumming behavior were observed for R. vespertilio .